/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.flink.configuration;

/**
 * A key with FallbackKeys will fall back to the FallbackKeys if it itself is not configured.
 */
public class FallbackKey {

	// -------------------------
	//  Factory methods
	// -------------------------

	static FallbackKey createFallbackKey(String key) {
		return new FallbackKey(key, false);
	}

	static FallbackKey createDeprecatedKey(String key) {
		return new FallbackKey(key, true);
	}

	// ------------------------------------------------------------------------

	private final String key;

	private final boolean isDeprecated;

	public String getKey() {
		return key;
	}

	public boolean isDeprecated() {
		return isDeprecated;
	}

	private FallbackKey(String key, boolean isDeprecated) {
		this.key = key;
		this.isDeprecated = isDeprecated;
	}

	// ------------------------------------------------------------------------

	@Override
	public boolean equals(Object o) {
		if (this == o) {
			return true;
		} else if (o != null && o.getClass() == FallbackKey.class) {
			FallbackKey that = (FallbackKey) o;
			return this.key.equals(that.key) && (this.isDeprecated == that.isDeprecated);
		} else {
			return false;
		}
	}

	@Override
	public int hashCode() {
		return 31 * key.hashCode() + (isDeprecated ? 1 : 0);
	}

	@Override
	public String toString() {
		return String.format("{key=%s, isDeprecated=%s}", key, isDeprecated);
	}
}
